Safety-envelop.



PATENTED APR. 21, 1908.

0. 0. BLAKE.

SAFETY ENVELOP. APPLICATION FILED MAY 17, 1906.

Witnesses i In V67? T0 7".

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UNITED sTA Es PATENT OFFICE.

CATHERINE C. BLAKE, OF ROUND GROVE TOWNSHIP, McLEOD COUNTY, MINNESOTA.

SAFETY-ENVELOP.

No. seams.

Application filed May 17, 1906.

To all whom it may concern:

Be it known that I, CATHERINE BLAKE, a citizen of the United States, residing in Round Grove township, in the county of Me- Leod and State of Minnesota, have invented a new and useful Improvement in Safety- Envelops, of which the following is a specification.

My invention relates to improvements in safety envelops, its object being to produce an envelop which, after being sealed, cannot be reopened without destroying or so defacing it that the fact of its having been opened will be apparent. By its use the danger of opening envelops for the purpose of surreptitiously reading letters or wrongfully removing remittances will be greatly reduced.

In the accompanying drawings forming part of this specification, Figure 1 is a perspective view of my envelop open; Fig. 2 is a plan view of the envelop closed, and Fig. 3 is a transverse section taken on the line XX of Fig. 2.

The blank from which the envelop is made may be cut in any usual or suitable form, but it is preferably made from heavy, easily compressed paper. The edge A of the flap B, which, in unsealed envelops, is free to open and close, is pressed into, or otherwise provided "with, corru ations O and is also formed with a reverse fold D parallel with the edge A. In the opposite or adhering flap E of the envelop a depressed panel F is formed, to which the mucilage (preferably of high grade) is ap lied. The lower and upper edges G and (g of this panel are provided with recesses H adapted to receive the edge A and fold D, respectively, of the free flap.

Specification of Letters Patent.

Patented April 21, 1908.

Serial No. 317,279.

The envelop may be sealed by moistening the mucilage in the panel F and then slipping the edge A and fold D of the free flap into the recesses II oi the opposite llap. \Vhen adhesion has taken place between the two 'l'laps of the envelop, it will be found impossible to reopen the same without mutilation.

Having described my invention, what I claim as new and desire to protect by Letters Patent, is:

1. In an envelop, a flap having a folded edge provided with transverse corrugations, in combination with a longitudinal quadrilateral panel extending partway across the opposite llap, and adapted to receive said corrugated edge.

2. In an envelop, a free llap having a reverse "fold near its edge and corrugations below said fold, in combination with'an adhering Ilap formed with a depressed quadrilateral panel having a longitudinal marginal recess on each side thereof, said anel being adapted to receive the corrugatec portion of the free flap.

3. An envelop comprising a body portion and a flap, said body portion bein formed with a depressed longitudinal pane l shorter than the envelop, and the flap being pro vided with corrugations adapted to be re ceived by the panel.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

OATHERIN E C. BLAKE.

I/Vitnesses:

E. SCHMlTZ, W. J. BLASS. 

